Handpiece



Nov. 13, 1928.

H. E. S. CHAYES ET AL HANDPIECE Filed Oct. 30, 1925 Patented Nov. 13, 1928.

UNITED STATE-s 'PATENT HERMAN E. S. CHAYES AND..A`UGST IP. J URGEN SEN, F. NEW YORK, N. Y., ASSIGNORS TO CHAYES DENTAL'INSTRUMENT CORPORATION, vOF NEW YORK, N. Y., A COR- PORATION yOF DELAWARE.

HANDPIECE. Y

Application mea october 30,1925. sex-iai No. 65,716.

rlihis invention relates to a dental handpiece, and has for its object to provide a khandpiece which is of light weight, perfectly balanced andy free from vibration, which I' comprises a minimum number of partsand whichcan be` readilyassembled and disassembled.

^ A further objectis theprovision of ahandpiece the barrel ofwhich is freely rotatable in a bracket, the bracket having a detachable swiveled connection with a hinged'a'rm. The handpiece is so constructed that it can readily be removed from its mounting and immersed in a sterilizing fluid without damage to any of its parts.

Y In the drawings, in which a preferred embodiment of the invention has been selected for illustration Fig. 1 is a view in side elevation of a handpiece embodying the invention.

an enlarged scale of the device shown in FiO. 1.

Fig. 3 is a detail longitudinal sectional view showing the construction of the spindle and chuck parts.

Fig. 4 is a detail sectional view of a mod-- pulweight, and having a grooved vand knurled portion 11 which facilitates the firm holding of the drill head in-thehand of the operator." The cylindrical casing. 10 vis provided at its forward end with' a tapering end section 12 formed ofjstainless steel or the like and arranged to serve as a bearing member inwhich the'forward end ofthe spindle structure is casing 10 by screw-threads 13,. y.

The rearward end of the Vcasing l0 has litted or secured thereon a sleeve 14 formed of bronze, steel or the like and adapted to'serve as a journal having a sw-iveled relation with ready referred to.

on vthe spindle` 21 journaled. The bearing member 124 is secured inthe forward end of the rmember 15 which, in relation with a pulley an angular bracket turn, has a swiveled supporting member 40 about an axisat right,

angles to the axis ofthe casing 10, as later referred to. Y

ATlhe rearward end of-thevcasing 19 is internally screw-threaded as at `16 to receive a screw-threaded bearing bushing 17 which may be longitudinally adjusted in the end of the casing 1Q"by. reason ofthe screwthreaded connection. In order to lock the bearing bushing 17 inv-a desired adjusted position, lock nuts 18 are providedon the bushing 17, the inner one of which is adapted*` its adjusted position, but also to hold the, Fig. 2 is a view in longitudinal section on swiveled parts 14 and 15` in their operable relation, the other end surface of the bracket member bearing against a shoulder y19 formed for the purpose on thebronze sleeve 14 The bearing bushing 17 forms a bearin for the sleeve 20 of steel or the like'secure on a hollow spindle member 21 so that the spindle member 21 is free to rotate withinthe bearing bushing 17. The hollow spindle member 21 may bemade of duralumin or like lightweight'metal and at its vforward end is provided with an extended journal piece 22, of steel or-the to by screw-threads, as shown, and which is journalledin the bearing 'member 12 al- .The hollow spindlemembier-21 is thereby provided with bearing supports at, or substantially at, yits opposite extremities, and y,is held against axial move-` like, connected therement by the engagement of the inner end of the bushing 17 with the flange 2,0a on the inner end ofthe sleeve 20.

,v In" order to yrotate the hollow spindle 21 i position ofthe pulley23 2 Legion' and the finger piece 25 by which the bearn piece 22, the chuck 32, and into the holing bushing 17 is adjusted in its seat. With thisV structural arrangement the adjusting members 18 and 25 are protected from accidental movement by the hands of the operator. 0n the other hand the covering up of these normally exposed members .prevents injury that might otherwise occur to the hands of the operator using the device. The hand-piece is through this arrangement left wholly free from obstructing parts from the forward edge of the pulley flange member 24 to the extreme tip vportion of the casing 10.- The pulley A 23 is clamped or secured' upon the 'rearmost extremityv ofl the spindle 21, by means of the clamping nut 35 which has `screw-threadedV engagement with a plurality of Vclamping jaws extending rearwardly from the pulley and litting about the spindle, and having conical surfaces 36a adapted to be engaged by a corresponding conical surface on the interior of the nut, so that by turning the nut in one direction or the other, the clamping jaws are caused to grip or release the Vspindle 21.

An important' feature of the invention resides in the construction by which the tool shafts are held in place in the hand'- pifece. This construction includes a longitudinally adjustable shaft or core member 27 which has a screw-threaded relation with the rearmost extremity of the hollow spindle member 21 as at 28 and extends forwardly into the hollow spindle member 21 to a position within the rear portion of the journal piece 22 carried by the end of hollow spindle member21. The forward extremity of the shaft 27 is hollowed out as at 29 to receive the end of the shaft 30 of a drill or other tool, such as a grinding stone 30a; The ex- Y treme forward portion of the hollow end of the shaft 27 is arranged to engage the rear- Inost end of a hollow chuck member 32, Figs, 2 and 3, which is longitudinally slit inwardly from its opposite ends ,for a portion of its' length as at 33. Thejextremities of the chuck vmember 82' are `beveled as is shown at`34 for engaging correspondingly beveled portions formed in the journal piece 22 and on the terminal portion of the shaft 27'. The beveled engagement of these parts is such that pressure exerted against the chuck member4 32 by the longitudinal movement ofthe shaft 27, causedl by rotating the shaft through the knurled finger piece 37 thereon, compresses or forces the flexible end port-ions of the chuck B2 inwardly against i the tool shaft 30 which may be contained therein; It will be seen that the clamping action which is thus exerted by the chuck member 32 against the contained shaft part 30 iwill hold the tool rigidly in its operating position. Also, the passing of the tool shaft through the bearing member 12, thel journal spindle member 21, by turning lo'w'ed-out portion 29 of the shaft 27, provides for the positive aligning ofthe tool shaft 230 with the axis of rotation of the spindle. The result is that the tool is smoothly driven without lateral vibration so that effectiveV work can ,be accomplished thereby.- L

In order to release a tool held by the chuck 32, the shaft 27 is reversely rotated through the knurled finger piece 37, moving the shaft rearwardly and thereby releasing the clutching engagement of the chuck member and permittingthe tool to drop from or 'be removed from its position in the for*V ward extremity of the device.

The shaft 27' and chuck removed from their positions in the hollow the threaded portion 28 Vof theV shaft entirely out of en-A gagement with the inner end of the hollow 82 may be readily spindle member 21. The shaft 27 may then be completely withdrawn from its position, wheretuionY the chuck member 32 will drop through the hollowA member 21 and out through the open end thereof.

The chuck member is as readily placed in i position within the hollow, spindle member 21 by merely dropping it into the open bore of the hollow spindle 21V and placing the inner shaft 27V in'positi-on. The inner shaft 2'( will inevitably take its proper engaging position with the rearmost end of the chuck 32.

The supporting bracket member 15 is swivele'd, as has pulley supporting member 40` on which the pulleys 41 are mounted one on each side thereof. The position of the pulleys 41 is so relatedjto that of the pulley'23 that a belt 42 may be passed around the pulleys 41 and overthel pulley 23 the belt extending suitable driving pulley, not shown. This insures a proper drivin@ of the pulley 23 in any position to which the handpiece may be moved about its lswivel connections. The pulley supporting member 40 is hinged at- 47 to a socketr member 43 which receives the end of a stem', not shown, on a bracket arm carried' by the power supplying device, the hinging Increment being limited by the engagement of the pulley shaft 48 with the socket member andV with a shoulder 49 thereon. The bracket member 15 is provided in the under portion thereof lwith an oil receiving opening 44 which, when `the parts are inverted,'leads; to a `corresponding opening 45 passing through the Vsleeve -14 and the wall of the casing 10'. By rotating the casing 10 in its seat inthe bracket 15` until aligned .marks which may be .provided are brought into proper position, oil dropped into the opening 44 will pass through the openings 45 into the annular channel 46 between the casing 10 andthe: rotatable hollow spindle alreadybeen stated, to the y toa' VF ig. 2, to thereby member 21. The oil having reached this chamber will iind its way to all parts of the relatively moving portions of the spindle and casing structure.

The barrel portion of the supporting bracket 15 is preferably of somewhat greater internal diameter than that of the sleeve 14 and is provded at each end of its bore with recesses adapted to receive bearing rings 15a which bear against said sleeve 14 and thus eliminate wear upon the bracket member which is preferably of a light weight metal. These rings also provide ciearance between sleeve 14 and bracket 15. which forms a lubricant reservoir 46a.

The swivel connection between the bracket member 15 and the pulley supporting member l10 comprises a pivot pin 50' seated or secured in the end portion of the bracket 15 and adapted to extend into a Vcentral aper# ture 51 in the pulley supporting member. The central aperture 51 is counter-bored at itsl outer end to receive a sleeve 52 which is forced therein and serves to hold in place a splt spring ring 53. The pivot pin 50y is provided with a groove or reduced portion 511 into which the spring ring 53 is adapted to snap when the parts are assembled, as in resiliently prevent withdrawal of the pivot pin and to connect the parts so that they may swivel with respect to each other.

A modified form of swivel connection is shown in Figs. land 5, in which a pivot pin 55 seated or secured in the end of the bracket 15 and is provided with an enlarged conical section 56 to provide an cess 57 at the junction of the conical portion with the end surface of the supporting bracket. The lower end of the pin 55 is adapted to extend into a central bore 58 in the pulley supporting member and this central bore is provided with two outer enlarged portions 59 and 60. The inner enlarged portion 59 forms a recess to receive a cylindrical member 61 having a plurality of spring arms 62, the outer ends of which are inturned as at 63 and thereby adapted to fit over the base portion of the conical portion 56 and to enter the recess 57 to thereby hold the parts in connected position while allowin them to swivel one with respect to the other.

annular re- The outer enlarged portion of the bore permits the necessary movement of thel spring arms 62.

With either form of swivel connection shown the vpulley supporting member 40 may be provided with a stop '64 adapted to co-act with a stop 65 on the bracket 15 to limit the extent of the swiveling movement in either direction.

It will be seen that the structure thus provided is relatively light in weight since all improved construction. The` able feature of the invent-ion. The device as a whole, is characterized by its simplicity of construction and the facility which is provided for adjusting or assembling the parts.

What is claimed is z* l. A dental handpiece comprising a casing, a bearing sleeve secured to said casing,

la bracket member having a barrel portion surrounding and spaced from said bearing sleeve, and bearing rings mounted in each end of said barrel port-ion and contacting with said bearing sleeve.

2. A dental handpiece comprising a casing, a bearing sleeve secured to said casing, a bracket memberhaving a barrel. portion surrounding and spaced from said bearing sleeve, bearing rings mounted in each end of said barrel portion and contacting with said bearing sleeve, an opening leading through the bracket to the space between the bracket and the bearing sleeve, ing from the spaceV between the bracket and the bearing sleeve to the interior of the casing.

1n testimony ywhereof we affix tures.

HERMAN E. S. CHAYES. AUGUST P. JURGENSEN.

and an opening leadour signa- 

